Field of the Invention
The present invention relates to a power supply apparatus that supplies electric power to an external electrical device, for example, an electric outboard motor.
Description of the Related Art
Japanese Patent Laid-Open No. 2011-213239 (Patent Document 1) and Japanese Patent Laid-Open No. 2011-213241 (Patent Document 2) each disclose a structure in which an electric outboard motor as an external electrical apparatus including an electric motor and a power supply apparatus or power supply unit that supplies electric power to the electric motor are configured as independent members. In the power supply apparatus disclosed in Patent Document 1 and Patent Document 2, a battery pack mount section including an opening to which a battery pack is mounted is provided on a side surface of a unit case, and the battery pack and the battery pack mount section are exposed to an outside of the unit case.
In general, most electric outboard motors are low-powered and used for small-sized fishing boats in many cases. Almost no small-sized fishing boat is equipped with a cabin (room) that can house a power supply apparatus (power supply device or unit), and hence, the power supply apparatus is generally installed on a deck of a hull (boat body).
If the power supply apparatus is unfortunately installed on the deck of the hull as described above, the power supply apparatus is exposed to rainwater and wave splashes. Hence, although countermeasures for preventing electric leakage, short circuit, and other problems due to the exposure to water are indispensable, Patent Documents 1 and 2 do not describe any countermeasures therefor.
Further, in Patent Document 1, the power supply apparatus is not provided with wheels, and hence, the power supply apparatus needs to be lifted up for its carriage. Particularly in a case where the battery pack has a high capacity, the carriage of the power supply apparatus is difficult.